Ferritic stainless steels have good properties for many uses that are not too demanding. For example, kitchen sinks, hubcaps, wheel covers and similar articles can be made of ferritic stainless steels. Ferritic stainless steel is strong, tough, corrosion resistant to environments found in uses such as those mentioned above, and it takes a high polish. In addition, the ferritic stainless steels, which usually contain about 13 % chromium and iron, are relatively inexpensive for stainless alloys.
For many such uses of ferritic stainless steel, it is necessary to subject the stainless steel to a deep drawing process. However, deep drawing processes produce a condition known as roping or ridging in steels that are not adapted to deep drawing. Roping and ridging is characterized by parallel marks in the direction in which the material was previsouly rolled which creates a poor appearance that cannot be removed by polishing but must be removed by grinding if indeed it can be removed at all.
Steels having high anisotropy have good deep drawing characteristics. A measure of anisotropy is a mathematical relationship among the plastic strain ratios in the direction of rolling, across the direction of rolling, and 45 percent to the direction of rolling. This relationship is indicated by the notation "R" and it is expressed as a number. The higher the number, the greater the anisotropy; and accordingly, the better the steel is for deep drawing. As an example, aluminum killed low carbon steel is an excellent steel for deep drawing, and it has an anisotropy (R) of about 1.6.